Oil burner unit



Ocf- 3, 1944- s. J. LEvlNE 2,359,567

OIL BURNER UNIT vFiled. May 2l, 1942 5 Samuel J. Levlne 220 Zi b 7 1 f Ls iVm/.76 M@ -@i 4 Hi'AttorneS;

Patented Oct. 3, 1944 @EL BRNER UNIT Samuei S. Levine, Verona, N. E., assigner to Qanerali Electric Company, a corporation ot New York applicaties may 2i, 1942, serial No. 443,960

s claims. (ci. e-7s) This invention relates to oil burners, and the principal ,object is to provide an improved form` of automatic, electrically operated oil burner unit suitable for application to various types of furnaces and boilers for operation under thermostatic control in domestic heating service.

The invention provides improvements upon the oil burner unit disclosed and claimed in thel junction with an air inlet skirt suspended therefrom adjacent to .the floor as a noise suppressing enclosing jacketior the other parts of the unit.

A further object is to provide a more quiet oil burner unit by having a vertical electric motor driven air compressor and oil pump mechanism resiliently seated in an adjustable height, floor mounted base to counterbalance a burner head projecting horizontally therefrom and by having a specially formed overhanging centrifugal blower scroll casing carried at the top of the mechanism with ,an'alr inlet skirt removably suspended therefrom adjacent to the floor for suppressing the noise of the mechanism while providing ready access to the various operating parts and connections of the unit.

Another object is to provide the under side of the blower casing within the skirt with both an annular air inlet mounting drum having flow equalizing ports and a cooperating adjustable band for restricting the air ilow and an offset air outlet orifice exibly connected with a special combined air and high voltage ignition transformer connection box formed at ,the inlet end of the burner nozzle so as to constitute a nonrectilinear series of sonic filter pulsation chambers of diifring size and shape along the path oi the air ilow for further dampening and suppressing both high pitched blower and low pitched combustion noise.

A still further object is to decrease the temperature rise of the burner head on shut-down by minimizing the heat storage capacity oi the parts and at the same time reducing the unbalancing eiect oi' the horizontally projecting burner head overhanging the supporting base. thereby enabling a specially formed lightweight base and burner head supporting structure to be employed..

A preferred embodiment of the invention is illustrated in the accompanyingA drawing in which Fig. 1 is a vertical sectional view of thev improved form of conversion oil burner unit; Fig. 2 is a top view of the unit with parts of thc overhanging blower casing broken away in order more clearly to reveal the details of construction oi' the burner head airinlet and supporting Vbox and the other parts of the unit located beneath the casing; Fig. 3 is a partial sectional view along the line 3-3 ofFig. 2 showing the vertical elec-Y tric motor driven oil pump and air compressor mechanism provided with the special inverted bell mounting for the blower and the concentric mounting for the annular air inlet drum around the bell; and Fig. 4 is a sectional view along the line 4-4 of Fig. 1 showing more clearly the construction of the various parts of the unit, particularly the scroll forming dividing wall and cut-ofi within the blower casing and also the removable access door with which the interconnected burner head air inlet and supporting box is provided.

Referring to Figs. 1 and 3. the vertical axis electric motor driven oil and air pressure supply mechanism I'U of the unit has a combined oil pump and air compressor I i mounted inside of the oil and air pressure sump I2 with the vertical shaft I3 carrying the rotary pump blade I4 and also the outeroverhanging rotor I5 of the induction type electric motor I6 having the outwardly open stator ileld structure Il. The oil pump and air compressor mechanism I0 serves to supply both oil and air under pressure to the horizontal oil and air discharge tubular burner head indicated generally by the reference character I8 and as shown is of the improved type described and claimed in the Lum Patent 2,032,- 291, granted February 25, 1936, although any other suitable type of oil pumping means may be employed if desired. Hence, the detailed strucl with suitable positioning bosses formed on the supporting base plate 24. Base plate 24 is provided with an enlarged central opening 25 for permitting the sump I2 to hang therethrough at a low level relative to the horizontally project-- ing tubular burner head -I8 so as to lower the center of gravity of the operating mechanism and thereby helpstabilize the unit upon the ad-.;

justable legs 26 for varying the height of the base plate 24 above the floor and for levelling 30 is provided with a special air flow guiding reentrant' mounting element 3| in the form of an inverted bell, as shown in Fig. 3, so that it may be mounted on the upper end of the motor driven shaft I3 by means of the holding-down nut 32. The split scroll casing 33 for blower 38 is formed of the lower plate 34 and the upper plate 35, each having a semicircular rounded end opposite a square end. The lower plate 34 is carried by the 'annular air inlet drum 36 which is secured in coaxial alignment with the blower wheel mounting bell 3|, as shown in Fig. 3, to the motor I6 by means of the resilient mounting washer 31 and the clamping screw 38so that the hum vibrations produced by the motor stator field |1 are not readily amplified by the blower casing structure. 'Ihe annular air inlet drum 38 is provided with a plurality of flow equalizing ports 39 with which the correspondingly apertured adjustable band 40 cooperates to vary the effective area of the inlet ports to the blower and thereby regulate the air flow. The lower plate 34 of the blower casing is provided with an upturned circular air inlet orifice 43 concentric with the annular air inlet drum 35 and the wheel mounting bell 3| but slightly eccentric with the semicircular end of the scroll casing 33 and through which the mounting bell 3| of the blower wheel 38 projects to form therewith an annular restricted opening from the air inlet drum 35 into the blower casing 33. The lower plate 34 also is provided with a rectangular air outlet opening 44 oiset from the air inlet opening 48 into one corner of the rectangular end of platev 34 and having downturned edges 44a for connection with the upwardly open air inlet box 45 of the air discharge nozzle tube 4G of the burner head I8 by means of the flexible joint 41, preferably formed of canvas or `other suitable material clamped to the upper edges of the box and the downturned edges 44a of the opening 44.

The top plate 35 of the blower casing as shown is pressed into a dome form with a depending rim so that the circular and rectangular edges thereof will match and engage with the corresponding edges of the lower plate 34.l Top plate 35 preferably is also provided with a suitably formed central strengthening rib 48 to prevent resonant deformation of the enlarged arched dome. Thus, as shown in Figs. 1 and 2, the two plates 34 and 35 constitute a flat blower casing of symmetrical form having a rounded end with the air inlet orifice 43 located centrally in the under side thereof, and having a square end with the air outlet opening 44 oilset l into a'corner thereof.

In order to provide a scroll passage 48 around the blower 38, as well as a dead air noise suppressing chamber 49 in the blower casing, a specially formed dividing wall 58 is interposed between the plates 34 and 35. Preferably, the dividing wall 58 is provided with suitable lugs 5|,

' as shown in Fig. 4, that interlock with corresponding slots formed in the bottom plate 54 to anchor the dividing wall 55 in its proper position. A specially rounded double wall cut-ofi' l vane k52 extends from the dividing wall 50 into proximity to the periphery of the blower 80 with --..fbothwalls of the cut-oil? vane in slightly spaced relatign with each of the blgwer asing'o arcing electrodes 82 that are located adjacent plates 34 and 35, thereby tending to prevent or suppress high pitched air noise vibrations at the blower cut-ofi.

The removable enclosing and air inlet skirt 65 for the unit is suspended from the blower casing, being secured to the edges thereof by the holding screws 5I so as to form a large air inlet chamber for the blower surrounding the air inlet drum 36. 'Ihe skirt 68 is formed into an arched or U shape with the edges inturned at both the bottom and top to fit the blower casing snugly with only an open gap at the square end 'so that the skirt may be readily removed from the unit upon loosening the screws 8l. This open arched or U shape with the inturned channel edges stifl'ens the enclosing skirt 50 sumciently to prevent vibration and insure that it remain properly suspended in position on lthe blower housing even though entirely unsupported at the bottom.

'I'he combined air inlet and high voltage ignition connection box 45 is formed by a special vertical channel brace member 65 having outturned edges 68 at the bottom thereof ilrmly joined to the base 24, preferably by welding, and the outturned edges 61 at the sides thereof similarly joined to the upturned end wall 58 of the base 24. Thus this special channel brace mem- -ber serves not only to form the open top 'air inlet box 45 but also to brace and stiffen the upturned wall 58 which is provided with the pressed out circular rim 18 projectin from the air box for mounting the outer air nozzle tube This ai-r nozzle tube. 45 preferably is formed of lightweight steel so 48 of the burner head I8.

that it may be readily welded into the rim 18 and carries the renewable cast iron nozzle tip 12 at the end thereof projecting into the furnace.

'I'he channel brace member 85 that cooperates with the base' 24 and the upturned end wall 68 thereof to form the combined air and connection box 45 is provided with a specially formed access door 15 having a central opening 15a and means for removably sealing therein the air pressure tube 'l5l and the oil pressure tube 11 which interconnect the inner oil atomizing nozzle 18 of the tubular burner head I8 with the electric motor driven oil and air pressure supply mechanism I8. This is accomplished by mounting the tubes 15 and 11 in sealed engagement with the enlarged central part 80 of the supporting strut 8| so as to slope away from nozzle 18 slightly.- Strut 8l has its ends bent over to be received into specially depressed slots 82 formed in the channel brace member adjacent the top and bottom edges of the access opening 88 that is covered by the access door 15. As shown more clearly in Fig. 4, the left-hand edges of the access opening 83 are pressed out into a semicircular channel shape for receiving the semicircular end of the access door 15 which is heldin with the inside of the outer air tube 48 of the` driven mechanism I intermediate its ends with the added weight of the blower housing and enclosing skirt tends to lessen the mechanical vibration of the mechanism. Also, the flexible 'air y 5 connection 41 tends to dampen mechanical vibrav tion. The light weight of the burner head parts tubular burner head I8 for supporting the inner nozzle 18 and the arcing electrodes 92 in proper position therein when the strut 8| is sealed in position by the access door 15.

In operation the ignition transformer 88 and the electric driving motor I8 of the air and oil supply mechanism I0 are suitably energized in proper sequence by means of any usual automatic oil burner control (not shown) so as to provide an ignition arc'adiacent the end of the oil atomizing nozzle 18 and also create a supply of oil and air under pressure in the sump tank I2. The admission of oil under pressure from the sump tank I2 to the atomizing nozzle 18 preferably is materially reduces the heat storage mass thereof so that when the operation of the burner is stopped, there is relatively little heat stored therel0 in to cause overheating of the oil nozzle 18. The

isolation of the highvoltage terminals of the ignition transformer 88 and the leads 89 therefrom within the air box 45 and the air tube 48 effectively prevents any accidental contact therewith and thereby makes the unit more safe for installation in the home. Still the access door 15 may be readily removed by the service man to permit the` oil atomizing nozzle 18 and its associated parts readily to be withdrawn from the air tube 48 for 20 inspection or repair through the opening`88 after controlled by an electromagnetic valve 81 shown diagrammaticaily in the drawing. The flow of combustion air from 'the blower 30 is regulated by loosening the clamping screw 4I and sliding the band 40 to vary the effective area of the equalizing ports 39 formed in the annular air inlet drum 38 thereby decreasing or increasing the amount of combustion air supplied to the nozzle tube 48. Due to the non-linear series of sonic.

filter ,pulsation chambers of different sizes and shapes formed along the path of the air flow, both the high pitched oscillations produced by the blower and the low pitched oscillations or rumble produced by combustion at the burner nozzle are effectively dampened and suppressed.

Thus the improved unit is exceptionally quiet since the air must flow from adjacent the oor outwardly around the base 24 and into a relative- 1y large annular sonic filter pulsation chamber defined by the base 24 and its upturned'righthand end 88, the arch channel enclosing skirt 80 and the lower plate 34 of the blower housing with the motor driven mechanism located centrally therein. The air flow then divides and passes inwardly through the flow equalizing openings 39 into a relatively small restricted annular chamber defined by the drum 38 and the mounting bell 3i of the blower as well as by the cooperating blower inlet orifice 43 and the outwardly open stator I1 and rotor I5 as shown in Fig. 3. Thus an effective noise suppressing action as well as increased cooling of the motor stator the ignition leads 89 are disconnected from the transformer terminals. What I claim as new vand desire. to secure by Letters Patent of the United States, is:

1. In an oil burner, a vertical axis blower casing having a round end opposite a square end and provided with an interior dividingr wall forming a blower scroll having an air inlet orifice and an air outlet opening formed in the under side of said casing with said orifice disposed eccentrically in said round end and said outlet opening offset into a corner of said square end, a U-shaped air inlet skirt suspended from the periphery of said blower casing and having a gap at the square 3;, end thereof, an upwardly open air-*box having a flexible 'joint for communicating with said outlet opening and having a lateral wall extension for substantially closing said gap and provided with a floor mounted base having the perimeter there- 4u of in spaced apart relation with said skirt adjacent the bottom edge thereof, an air discharge nozzle tube projecting from said air box through said gap, and a vertical axis electric motor driven oil and atomizing air pumping mechanism re- 45 siliently seated in said base and provided with mounting means for carrying said blower casing over the top thereof and having an oil discharge nozzle mounted in said air nozzle tube and acombustion air blower wheel rotatable at the top thereof in said blower scroll.

and rotor results from the rapid annular blower f i ing said orifice and having a plurality` of ow inlet air ow provided by orifice 43, drum 88 and bell 3i during operation of the unit. Then, after passing through the blades of the centrifugal fan 30, the air ows around through the scroll shaped chamber formed by the fan housings 34 and 35 in conjunction with the dividing wall 58 and the cut-ofi 52 and is then diverted through the flexible joint 41 into the rectangular air box 45 wherein the air flow is again diverted and finally passes through the cylindrical air tube 48 and the noz-l l 2. In an oil burner, a vertical axis blower casing having an airinlet orifice formed in the under side of said casing and a dividing wall forming a scroll about said orifice, an inlet drum surroundequalizing ports and adjustable means for varying the effective area of said ports to regulate the air flow, an air inlet skirt suspended from said casing around said drum and having a gap at one side thereof, an air outlet box communicating with the under side of said casing and having a wall extended for substantially closing said gap and provided with a oor mounted base disposed within said skirt, an air discharge noz- 05 zle tube projecting from said box, and a vertical axis electric motor driven oil and atomizing air pumping mechanism carried within said skirt by said base and provided with mounting means for engaging with said inlet drum to carry said blower casing-over the top of said mechanism and having an oil discharge nozzle mounted in said air nozzle tube and a combustion air blower wheel provided with a re-entrant lmounting bell projecting through said drum and inlet orifice for rotation of said wheel in said blower casing.

3. In an oil burner, a vertical axis blower casing having an air inlet orice formed in the under side of said casing and a dividing wall forming a scroll about said orifice, an air inlet skirt suspended from said casing and having a gap at one side thereof, an air outlet box communicating with the under side of said casing and having a wall extended for substantially clos/ing said gap' and provided with a oor mounted/'base disposed within said skirt, an air discharge nozzle tube mounted in and projecting from said box, and a vertical axis electricv motor driven oil and atomizing air pumping mechanism carried by said base and provided with mounting means for carrying said blower casing over the top thereof and having an oil discharge nozzle mounted in said air nozzle tube and a combustion air blower 1 wheel rotatable at the top of Saidmechanism in said casing.

4. In an oil burner, a vertical axis blower casing having an air inlet orice formed in the under sidec of said casing, an air inlet skirt suspended from said casing and having a gap at one side thereof, means for substantially closing said gap including an air outlet box communicating with the under side of said casing and provided with a floor mounted base disposed within said skirt, an air discharge nozzle tube projecting from said box, and a vertical axis electric motor driven oil and atomizing air pumping mechanism carried by said base and provided with mounting means for carrying said blower casing over the top thereof and having an oil discharge nozzle mounted in said air nozzle tube and a combustion air blower wheel rotatable at the top of said mechanism in said casing.

5. In an oil burner, a vertical axis electric motor driven oil and atomizing air supply mechanism having a centrifugal blower at the top thereof, a blower casing carried by and overhanging said mechanism and having both an air inlet orice concentric with said blower and an Aoffset air outlet opening formed in the under side of said casing, a horizontal oil and air discharge burner head having an oil supply connection with said mechanism and having an upwardly open air inlet box disposed beneath said outlet opening and communicating therewith, a base plate extending laterally from said air box for supporting said mechanism and said head, and an air inlet skirt suspended from said casing in spaced apart relation with the perimeter of said base to form an air inlet chamber for said blower casing sur-` rounding said mechanism.`

6. In an oil burner, a vertical axis electric motor driven oil and atomizing air supply mechanism having an overhanging blower casing mounted at the top thereof, a horizontal oil and air discharge burner head having an oil supply connection with said mechanism and having an upwardly open air inlet box at one end thereof disposed beneath said casing and communicating therewith, a iioor mounted base extending laterally from said air box for supporting said mechanism and said head, and an air inlet skirt suspended from said casing to form an air inlet chamber for said casing surrounding said mechanism.

'1. In an oil burner, a floor mounted horizontal base having an upright wall, a vertical channel brace member secured to said base and Wall to form an open top air box, an air discharge nozzleltube mounted in said wall in communication with said air box, an oil nozzle mounted inside said tube, and a vertical axis electric motor driven oil and atomizing air supply mechanism carried on said base and having a vertical axis blower casing mounted over the top of said mechanism and overhanging said air box and provided with an outlet communicating therewith and an oil supply conduit removably mounted in a wall of said air box and communicating with said oil nozzle.

8. An oil burner unit having, in combination, a oor mounted vertical axis electric motor driven oil burner mechanism having a downwardly open blower wheel at the top thereof, a burner head connected with and horizontally projecting from said mechanism and provided with an upwardly open air inlet box beside said mechanism, a closed top blower casing for said wheel overhanging said mechanism, said casing having a round end opposite a square end and having an air inlet orifice and an air outlet opening formed in the under side thereof with said orifice disposed below said ,wheel in said round end and said outlet opening oiiset into a corner of said square end above said air box to communicate therewith, and an air inlet skirt suspended from the periphery of said casing adjacent to the :door to form jointly with said casing and air box an air inlet chamber coinmunicating with said blower air inlet oriiice and substantially surrounding said mechanism.

SAMUEL J. LEVINE. 

